hyperspec - The Common Lisp HyperSpec

The Common Lisp HyperSpec is not the ANSI Common Lisp standard, but is
based on that standard (with permission from ANSI and X3).
As an official reference to the Common Lisp language, hardcopy
documentation of ANSI Common Lisp, (American National Standard X3.226)
from ANSI is always definitive.
The hypertext markup for this document was created by Kent Pitman,
with the aid of a custom program written in Common Lisp and created
specifically for this task. Funding for the markup task was provided
by and copyright of the result is owned by The Harlequin Group Limited.